化感作用及其在环境保护中的应用

生物体产生生物活性物质即化感物质在生物体之间传递信息并导致生物质相互作用，这称为化感作用。化感作用是一个崭新的研究领域。本文介绍了化感作用的概念、分类、不同生物体之间比感作用的作用机理，着重论述了化感作用在环境保护中的应用途径、实例及建议。     

金鱼藻中抑藻化感物质的研究

通过静态模拟实验,比较了单独培养和共生培养下,不同初始藻密度时金鱼藻生物量和铜绿微囊藻密度的变化.采用固相萃取的方法对金鱼藻种植水中的化感物质进行富集,经甲醇洗脱、高效液相色谱分析,发现在铜绿微囊藻生长的胁迫下,金鱼藻释放的化学物质组成和含量发生变化,强极性物质含量下降,弱极性物质含量增加.二氯甲烷洗脱物经色谱质谱分析后,检测出15种不同于铜绿微囊藻释放的化合物,其中N-苯基-2-萘胺、脱氢枞酸甲酯和脱氢枞酸乙酯已有文献报道对藻类具有化感作用.     

作物秸秆对铜绿微囊藻的抑制作用

通过室内模拟实验研究了大麦、水稻和小麦3种作物秸秆对铜绿微囊藻(Microcystis aeruginosa)的抑制作用，并计算了不同秸秆的抑制率和抑制中浓度（EC₅₀）。研究结果表明，大麦秸秆、水稻秸秆和小麦秸秆对铜绿微囊藻的生长有显著的抑制作用，而且随着培养时间和秸秆投加量的增加，抑制作用提高。处理96 h后大麦和水稻秸秆处理下的铜绿微囊藻几乎全部死亡，表明本研究所用不同作物秸秆对铜绿微囊藻的生长有显著的抑制效果。研究结果还表明，大麦、水稻和小麦秸秆对铜绿微囊藻的72 h-EC₅₀由大到小依次是大麦>水稻>小麦，分别为248、334和1 943 mg/L，表明不同植物的秸秆对藻类的影响作用不同。分析3种秸秆抑制铜绿微囊藻生长的原因可能是3种植物秸秆在好氧的条件下可以分解产生多种具有抑藻作用化学物质，如有机酸、含甲基的酚类物质、醇类和酮类物质等，这些物质通过化感作用抑制铜绿微囊藻的生长，尤以大麦秸秆作用最为明显。     

不同质量浓度黄莒蒲和狭叶香蒲对铜绿微囊藻的化感作用

分别采用黄菖蒲（IrispseudacorusL．）、狭叶香蒲（TyphaangustifoliaL．）和铜绿微囊藻（Microcystisaeruginosa）共生培养的实验方法研究了不同质量浓度黄菖蒲、狭叶香蒲对铜绿微囊藻的化感作用。结果表明，黄菖蒲在质量浓度大于10g／L时对初始密度为1．0×10^7ind／mL的铜绿微囊藻具有较好的抑制作用，表现为黄菖蒲质量浓度为10、20和40g／L时，第15天对铜绿微囊藻的抑制率分别为30．1％、51．8％和84．0％；狭叶香蒲在质量浓度大于20g／L时对铜绿微囊藻有明显的抑制作用，表现为狭叶香蒲质量浓度为20g／L和40g／L时，第15天对铜绿微囊藻的抑制率分别为34．2％和77．7％，实验过程中，铜绿微囊藻叶绿素a含量逐渐减少，而藻密度、SOD活性及MDA含量先增加后逐渐降低，表明经过一段时间持续地化感胁迫，黄菖蒲和狭叶香蒲可以诱导铜绿微囊藻产生氧化胁迫，导致细胞结构严重损伤和叶绿素大量分解，从而强烈抑制铜绿微囊藻的生长。     

不同质量浓度黄菖蒲和狭叶香蒲对铜绿微囊藻的化感作用简

分别采用黄菖蒲（Iris pseudacorus L.）、狭叶香蒲（Typha angustifolia L.）和铜绿微囊藻（Microcystis aeruginosa）共生培养的实验方法研究了不同质量浓度黄菖蒲、狭叶香蒲对铜绿微囊藻的化感作用。结果表明，黄菖蒲在质量浓度大于10 g/L时对初始密度为1.0×10⁷ ind/mL的铜绿微囊藻具有较好的抑制作用，表现为黄菖蒲质量浓度为10、20和40 g/L时，第15天对铜绿微囊藻的抑制率分别为30.1%、51.8%和84.0%；狭叶香蒲在质量浓度大于20 g/L时对铜绿微囊藻有明显的抑制作用，表现为狭叶香蒲质量浓度为20 g/L和40 g/L时，第15天对铜绿微囊藻的抑制率分别为34.2%和77.7%，实验过程中，铜绿微囊藻叶绿素a含量逐渐减少，而藻密度、SOD活性及MDA含量先增加后逐渐降低，表明经过一段时间持续地化感胁迫，黄菖蒲和狭叶香蒲可以诱导铜绿微囊藻产生氧化胁迫，导致细胞结构严重损伤和叶绿素大量分解，从而强烈抑制铜绿微囊藻的生长。     

广玉兰、龙爪槐和黄杨化感物质对铜绿微囊藻生长的抑制

针对水华的主要物种——铜绿微囊藻,初步测定了60种植物的浸提液对其细胞增殖的抑制率。结果表明,8种植物的浸提液对铜绿微囊藻生长的抑制率达到90%以上。其中,广玉兰、龙爪槐和黄杨叶片浸提液对铜绿微囊藻生长的抑制率分别达到97.4%、95.6%和91.2%。通过计算得到培养7d后广玉兰、龙爪槐和黄杨的50%抑制效应质量浓度(EC50)分别为0.52、1.04、5.87g/L,而90%抑制效应质量浓度(EC90)分别为3.79、6.45、9.09g/L。首次发现此3种植物浸提液中富含能抑制铜绿微囊藻细胞增殖的化学物质,可以作为抑藻化感物质的一个重要来源。根据EC50和EC90对培养时间的拟合方程判断,广玉兰和龙爪槐浸提液对铜绿微囊藻的抑制效果较黄杨浸提液更为长效,且由于其抑制效果优于农作物秸秆,具有进一步研究的价值。     

不同质量浓度苦草对铜绿微囊藻生长及抗氧化酶系统的影响

采用苦草（Vallisneria spiralis Linn.）和铜绿微囊藻（Microcystis aeruginosa）共生培养的实验方法,通过追踪测定铜绿微囊藻的生物量、叶绿素a含量、丙二醛（MDA）含量、超氧化物歧化酶（SOD）和过氧化物酶（POD）活性,研究了不同质量浓度苦草对铜绿微囊藻生长及抗氧化酶系统的影响。结果表明,质量浓度大于10 g/L时,苦草对铜绿微囊藻有明显的抑制作用,表现为苦草质量浓度为10、20和40 g/L时,第15天对铜绿微囊藻的抑制率分别为63.3%、94.7%和99.8%,培养过程中,铜绿微囊藻的叶绿素a含量逐渐减少,而SOD、POD活性及MDA含量呈现先增加后逐渐降低的趋势,表明苦草释放的化感物质在经过一定时间积累后能够明显抑制铜绿微囊藻SOD和POD的活性,引起细胞的氧化损伤,促进叶绿素的分解,从而导致藻类死亡,这是苦草抑制铜绿微囊藻生长的原因之一。     

污泥干化焚烧联用系统最佳运行工况研究

污泥干化焚烧联用系统将污泥焚烧产生的能量用于污泥干化,可实现污泥处理的节能降耗。对于污泥干化焚烧联用系统的运行,进厂污泥负荷、初始含水率、热值、污泥干化目标含水率是最大的影响因素。为实现污泥干化焚烧联用系统的低能耗和安全稳定运行,结合国内某污泥干化焚烧处理工程,建立了污泥干化焚烧联用系统能量和物料平衡模型,在此基础上研究了变工况条件下污泥干化焚烧联用系统的运行模式,分析了运行负荷、污泥热值、进厂污泥含水率、入炉污泥含水率发生波动时,对污泥干化单元和污泥焚烧单元所产生的影响,并提出了对应的运行策略。     

底泥中降解邻苯二甲酸二甲酯菌群的特性研究

为了有效去除感潮河道底泥中邻苯二甲酸二甲酯(DMP),从深圳市某受DMP污染的感潮河道底泥中富集驯化出了一个土著DMP高效降解功能菌群(命名为菌群ZM),确定了菌群ZM的优势功能菌属,探究了pH、温度、盐度对其降解DMP的影响,研究了其在模拟底泥中的DMP降解性能。结果表明,变形杆菌门(Proteobacteria)α-变形菌纲(α-Proteobacteria)的新鞘氨醇杆菌属(Novosphingobium)是最主要的DMP降解功能菌。pH为6、温度为35℃是菌群ZM降解DMP的最佳条件。菌群ZM在盐度0.05%～1.00%内表现出较好的耐受性。菌群ZM在2 d内可以降解模拟底泥中70%的DMP(初始质量浓度100 mg/kg)。综上,菌群ZM在处理感潮河道底泥中DMP污染问题上具有一定的实际应用潜力。     

城市污泥微波干化工艺及干化特性研究

采用微波和烘箱结合及全程烘箱2种方式对城市污泥干化进行对比研究,考察了不同粒径、微波干化预处理、预处理时间及烘箱温度对污泥干燥特性的影响。结果表明,同一温度条件下,微波预处理时间越长,污泥干化速率越快。最优条件下,全程烘箱污泥达到最大干化速率的含水率为77%。微波干燥污泥具有时间短、干燥速率大的特点,微波和烘箱结合对比全程烘箱干化速率高且能耗低。     

The extract of aquatic macrophyte Carex cinerascens induced colony formation in bloom-forming cyanobacterium Microcystis aeruginosa

Environmental Science and Pollution Research - Colony formation in Microcystis aeruginosa played important roles in blooms formation. To study the effects of plant allelopathy on colony formation...     

Mechanistic insight into the inhibitory effect of artemisinin sustained-release inhibitors with different particle sizes on Microcystis aeruginosa

Environmental Science and Pollution Research - Environment-friendly algaecides based on allelopathy have been widely used to control harmful algal blooms. In this research, micro and nano scale...     

植物抗逆性研究进展

本文论述了逆境对植物各方面造成的伤害及植物产生的相应反应 ,重点对植物在生理生化上的变化、对抗性生理领域中的一些学说和最新研究结果作了介绍 ,并指出相生相克现象也可作为抗逆生理的一个方面加以研究 ,概念扩展后的抗逆生理学必将在农业、环保等方面得到更广泛的应用     

Allelopathic potential of oil seed crops in production of crops: a review

Agricultural production enhancement has been realized by more consumption of fossil energy such as fertilizer and agrochemicals. However, the production provides the present human with sufficient and diversified commodities, but at the same time, deprives in some extent the resources from the future human as well. In the other hand, it is known that synthetic herbicides face worldwide threats to human’s health and environment as well. Therefore, it is a great challenge for agricultural sustainable development. The current review has been focussed on various oilseed crop species which launch efficient allelopathic intervention, either with weeds or other crops. Crop allelopathic properties can make one species more persistent to a native species. Therefore, these crops are potentially harmful to both naturalized as well as agricultural settings. On the other side, allelopathic crops provide strong potential for the development of cultivars that are more highly weed suppressive in managed settings. It is possible to utilize companion plants that have no deleterious effect on neighbor crops and can be included in intercropping system, thus, a mean of contributing to agricultural sustainable development. In mixed culture, replacement method, wherein differing densities of a neighbor species are planted, has been used to study phytotoxic/competitive effects. So, to use alternative ways for weed suppression has become very crucial. Allelochemicals have the ability to create eco-friendly products for weed management, which is beneficial for agricultural sustainable development. Our present study assessed the potential of four oilseed crops for allelopathy on other crops and associated weeds.     

Complex interactions between autotrophs in shallow marine and freshwater ecosystems: implications for community responses to nutrient stress

The relative biomass of autotrophs (vascular plants, macroalgae, microphytobenthos, phytoplankton) in shallow aquatic ecosystems is thought to be controlled by nutrient inputs and underwater irradiance. Widely accepted conceptual models indicate that this is the case both in marine and freshwater systems. In this paper we examine four case studies and test whether these models generally apply. We also identify other complex interactions among the autotrophs that may influence ecosystem response to cultural eutrophication. The marine case studies focus on macroalgae and its interactions with sediments and vascular plants. The freshwater case studies focus on interactions between phytoplankton, epiphyton, and benthic microalgae. In Waquoit Bay, MA (estuary), controlled experiments documented that blooms of macroalgae were responsible for the loss of eelgrass beds at nutrient-enriched locations. Macroalgae covered eelgrass and reduced irradiance to the extent that the plants could not maintain net growth. In Hog Island Bay, VA (estuary), a dense lawn of macroalgae covered the bottom sediments. There was reduced sediment-water nitrogen exchange when the algae were actively growing and high nitrogen release during algal senescence. In Lakes Brobo (West Africa) and Okeechobee (FL), there were dramatic seasonal changes in the biomass and phosphorus content of planktonic versus attached algae, and these changes were coupled with changes in water level and abiotic turbidity. Deeper water and/or greater turbidity favored dominance by phytoplankton. In Lake Brobo there also was evidence that phytoplankton growth was stimulated following a die-off of vascular plants. The case studies from Waquoit Bay and Lake Okeechobee support conceptual models of succession from vascular plants to benthic algae to phytoplankton along gradients of increasing nutrients and decreasing under-water irradiance. The case studies from Hog Island Bay and Lake Brobo illustrate additional effects (modified sediment-water nutrient fluxes, allelopathy or nutrient release during plant senescence) that could play a role in ecosystem response to nutrient stress.     

巢湖湖岸砂石的磷吸附特性研究

以巢湖湖岸上富含铁、铝、锰等元素的砂石为实验材料,研究其对水体中磷的吸附效果。实验表明:在砂石对磷的吸附过程中,同时存在着物理吸附和化学吸附,且以化学吸附作用为主,符合准二级动力学模型;砂石对磷的作用与溶液初始磷浓度有关,磷释放与吸附的临界浓度点约为0.04 mg/L;砂石对磷的吸附符合Langmuir等温吸附方程,最大吸附量约为1 428.57 mg/kg,对磷的吸附效果比普通沙石要好,且经济易得。     

UASB反应器处理生活污水的试验研究

采用UASB中试(100 m3/d)对生活污水处理进行了研究。试验结果表明,采用此系统处理生活污水,出水水质良好。COD的去除率在52%~83%,出水的COD值<100 mg/L以下,SS的去除率在95%左右,UASB处理生活污水的最佳停留时间为6 h。产气率在0.1 m3/d。不管停留时间在10 h、5 h,出水的氨氮、乙酸值比进水的高;钙、镁、总氮、总磷、硫酸根和硝酸根离子出水值比进水值低。     

污泥淤砂分离器对分离分流污泥性质的影响

为解决我国很多城镇污水厂活性污泥的MLVSS/MLSS普遍偏低,污泥中泥沙淤积严重的问题,根据水力旋流器的分离原理,开发了污泥淤砂分离器,实现污泥中生物基质和淤砂的分离分流,研究污泥淤砂分离器主要结构参数排口比(底流口直径/溢流管直径)对分离分流污泥性质的影响。实验结果表明,排口比为0.4时,污泥经过污泥淤砂分离器后,得到的底流污泥MLVSS/MLSS比原污泥减小了34%,溢流污泥MLVSS/MLSS增大了16.8%,污泥中的生物基质富集在溢流污泥中,淤砂富集在底流污泥中;底流污泥浓度MLSS比原污泥增加了2.6倍,底流污泥SVI和CST分别减小了68%和70%,底流污泥浓缩效果明显,沉降性能和脱水性能大幅提高,有利于底流污泥的处理处置;进一步减小排口比,底流污泥浓缩效果、沉降性能和脱水性能均进一步提高。     

Status and trends of mercury pollution of the atmosphere and terrestrial ecosystems in Poland

The goal of this paper is to assess the current status and trends of total mercury (THg) contamination of the atmosphere and terrestrial ecosystems in Poland. The study shows that the reduced domestic and worldwide atmospheric emission of Hg resulted in decreased THg level in the terrestrial biotope and biosphere. Considering that Poland is one of the main Hg emitters in Europe, the THg concentrations in its abiotic environment are still elevated. However, the THg level in terrestrial organisms is relatively low, which is because a large proportion of Hg deposited on land is accumulated in organic-rich soils. Regarding the THg concentration, consumption of wildlife and livestock from Poland is safe for humans. Nevertheless, the authors indicate the need for effective environmental monitoring, based on selected bioindicators, which is crucial considering the slowing reduction of Hg emission combined with the consequences of the changing climate.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-021-01505-1.     

废电池中氧化锰还原冶炼锰钢的实验研究

为促进我国锌锰废电池集中资源化处理,开发了一种高温回收废电池中锰的新工艺.废电池分选后,破碎和筛分,其中二氧化锰与还原剂碳制成球团,烧结后在感应炉中还原锰,制成锰钢.实验表明,球团中不加表面活性剂的二氧化锰还原率为34%,球团中加入硫化物表面活性剂促进二氧化锰在钢中的还原率,达到80%,钢液中锰含量可达3.97%,本实验条件下,还原最佳时间为20 min.在铸钢生产中可以直接应用该工艺处理废电池.